1. Field
Embodiments of the present invention relate to an apparatus and method for detecting surface shear force on a display device.
2. Related Art
Display devices have become increasingly popular and are widely used, such as in cell phones, computer monitors, televisions, tablets, etc. These display devices may be any type of display, including an organic light emitting display (OLED), a liquid crystal display (LCD), etc. In particular, display devices including optical sensors have been developed, for example, to detect a user's interaction with the display device (e.g., an interaction with the display device via the user's finger or via the user's use of a stylus).
However, although display devices are able to detect a position of a user interaction (e.g., a user's touch), display devices have been limited in the ability to detect pressure of a touch interaction by the user. In particular, display devices are limited in the ability to sense a shear force (or shearing force) exerted by a user upon the display device. An example of a shear force interaction with a display device could be when a user applies pressure with the user's finger at a point on the display device and, while maintaining the position and the downward force of the finger, applies an isometric horizontal force (a shearing force) in any direction along the surface of the display device.
A display device capable of sensing a user's shear force upon the device is desirable, as this capability expands the breadth of interaction between a user and the display. Furthermore, a display device capable of sensing a shear force that is easy and inexpensive to manufacture is also desirable.